core: vm: sqlvm: return a bool from DecimalEncode and DecimalDecode

Instead of returning a fixed error code, we can return a boolean here
because the only possibility of an error is invalid arguments. Callers
of these functions must know where invalid arguments come from, and
correctly handle it by converting it to an error struct or panicking.

1 files changed, 28 insertions, 24 deletions

diff --git a/core/vm/sqlvm/runtime/instructions.go b/core/vm/sqlvm/runtime/instructions.go
index 6fa72d61a..35d3135b2 100644
--- a/core/vm/sqlvm/runtime/instructions.go
+++ b/core/vm/sqlvm/runtime/instructions.go
@@ -188,16 +188,16 @@ func decode(ctx *common.Context, dt ast.DataType, slot dexCommon.Hash, bytes []b
 	case ast.DataTypeMajorFixedBytes, ast.DataTypeMajorAddress:
 		rVal.Bytes = bytes
 	case ast.DataTypeMajorBool, ast.DataTypeMajorInt, ast.DataTypeMajorUint:
-		d, err := ast.DecimalDecode(dt, bytes)
-		if err != nil {
-			return nil, err
+		d, ok := ast.DecimalDecode(dt, bytes)
+		if !ok {
+			panic(fmt.Sprintf("DecimalDecode does not handle %v", dt))
 		}
 		rVal.Value = d
 	}
 	if major.IsFixedRange() || major.IsUfixedRange() {
-		d, err := ast.DecimalDecode(dt, bytes)
-		if err != nil {
-			return nil, err
+		d, ok := ast.DecimalDecode(dt, bytes)
+		if !ok {
+			panic(fmt.Sprintf("DecimalDecode does not handle %v", dt))
 		}
 		rVal.Value = d
 	}
@@ -1607,16 +1607,16 @@ func (r *Raw) castValue(
 	ctx *common.Context,
 	origin, target ast.DataType,
 	l int, signed, rPadding bool) (err error) {
-	oBytes, err := ast.DecimalEncode(origin, r.Value)
-	if err != nil {
-		return
+	oBytes, ok := ast.DecimalEncode(origin, r.Value)
+	if !ok {
+		panic(fmt.Sprintf("DecimalEncode does not handle %v", origin))
 	}
 
 	bytes2 := r.shiftBytes(oBytes, l, signed, rPadding)
 
-	r.Value, err = ast.DecimalDecode(target, bytes2)
-	if err != nil {
-		return
+	r.Value, ok = ast.DecimalDecode(target, bytes2)
+	if !ok {
+		panic(fmt.Sprintf("DecimalDecode does not handle %v", target))
 	}
 
 	err = flowCheck(ctx, r.Value, target)
@@ -1644,9 +1644,10 @@ func (r *Raw) castInt(ctx *common.Context, origin, target ast.DataType) (err err
 			return
 		}
 
-		r.Bytes, err = ast.DecimalEncode(mockDt, r.Value)
-		if err != nil {
-			return
+		var ok bool
+		r.Bytes, ok = ast.DecimalEncode(mockDt, r.Value)
+		if !ok {
+			panic(fmt.Sprintf("DecimalEncode does not handle %v", origin))
 		}
 		r.Value = decimal.Zero
 	case ast.DataTypeMajorFixedBytes:
@@ -1654,9 +1655,10 @@ func (r *Raw) castInt(ctx *common.Context, origin, target ast.DataType) (err err
 			err = se.ErrorCodeInvalidCastType
 			return
 		}
-		r.Bytes, err = ast.DecimalEncode(origin, r.Value)
-		if err != nil {
-			return
+		var ok bool
+		r.Bytes, ok = ast.DecimalEncode(origin, r.Value)
+		if !ok {
+			panic(fmt.Sprintf("DecimalEncode does not handle %v", origin))
 		}
 		r.Value = decimal.Zero
 	case ast.DataTypeMajorBool:
@@ -1677,9 +1679,10 @@ func (r *Raw) castFixedBytes(ctx *common.Context, origin, target ast.DataType) (
 			err = se.ErrorCodeInvalidCastType
 			return
 		}
-		r.Value, err = ast.DecimalDecode(target, r.Bytes)
-		if err != nil {
-			return
+		var ok bool
+		r.Value, ok = ast.DecimalDecode(target, r.Bytes)
+		if !ok {
+			panic(fmt.Sprintf("DecimalDecode does not handle %v", target))
 		}
 		r.Bytes = nil
 	case ast.DataTypeMajorFixedBytes:
@@ -1701,12 +1704,13 @@ func (r *Raw) castAddress(ctx *common.Context, origin, target ast.DataType) (err
 	switch tMajor {
 	case ast.DataTypeMajorAddress:
 	case ast.DataTypeMajorInt, ast.DataTypeMajorUint:
-		r.Value, err = ast.DecimalDecode(
+		var ok bool
+		r.Value, ok = ast.DecimalDecode(
 			target,
 			r.shiftBytes(r.Bytes, int(tMinor)+1, false, false),
 		)
-		if err != nil {
-			return
+		if !ok {
+			panic(fmt.Sprintf("DecimalDecode does not handle %v", target))
 		}
 		err = flowCheck(ctx, r.Value, target)
 		if err != nil {